Legacy System Extension (OSX-Elektron popup)

So I turned on my Mac (with Catalina) after a few days of it being powered off and my system showed me this pop-up:

“Legacy System Extension
Existing software on your system loaded a system extension signed by “Elektron Music Machines MAV AB”, which will be incompatible with a future version of macOS. Contact the developer for support.”

The Digitone was powered off and Overbridge wasnt running (autostart at login is disabled). I havent run updates or anything…

What is this legacy thing? Apparently I have to contact Elektron?
I don’t like popups.

Clicking “more info” took me here: About system extensions and macOS - Apple Support